Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . warella) nibelae sp. nov. Holotype whorl section, x 1. more compressed, and at larger diameters tends towards weakening of theexternal tubercles over the venter. The exact horizon from which this specimen was collected at locality 110is not known, but as far as the authors can recall, it was found high up in thesequence, above the level of abundant menabitids. This could possibly indicateyet another trend towards recoiling in the texanitids, possibly starting with arelatively evolute form such as M.
Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . warella) nibelae sp. nov. Holotype whorl section, x 1. more compressed, and at larger diameters tends towards weakening of theexternal tubercles over the venter. The exact horizon from which this specimen was collected at locality 110is not known, but as far as the authors can recall, it was found high up in thesequence, above the level of abundant menabitids. This could possibly indicateyet another trend towards recoiling in the texanitids, possibly starting with arelatively evolute form such as M. {A.)falloti through M. {Delawarella) jeannetito the present species. Occurrence Campanian of Zululand. Menabites {Delawarella) sp. 262 Material SAM-PCZ5692, locality 110, south-western tip of the Nibela Peninsula,Zululand, St Lucia Formation, Campanian II. Description A single septate specimen consisting of approximately a quarter of awhorl is referable to M. {Delawarella), although specific identification is notpossible. CRETACEOUS FAUNAS FROM SOUTH AFRICA 343. C —- ^ ^^ D Fig. 262. Menabites (Delawarella) sp. indet. SAM-PCZ5692. X 1. 344 ANNALS OF THE SOUTH AFRICAN MUSEUM The whorl section is ovoid, wider than high with a prominent dorsal zoneof impression, a vertical umbilical wall and gently rounded flanks converging toa broadly rounded venter. The keel is broad and low, and distinctly undulating,though it is not quite clear if the undulations correspond to the externaltubercles. Save slight undulations, all lateral ornament is absent, with only umbilical(1) and external (5) tubercles present. The umbilical nodes are rounded toslightly radially elongated. The external tubercles are clavate and obliquelyaligned in a forward direction. The ratio of external to umbilical tubercles isof the order of three to one. The suture is beautifully exposed as seen in Figure 262. Discussion Despite the fragmentary nature of this specimen, it differs from all knownZululand spe
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Keywords: ., bookcentury1800, bookdecade1890, booki, booksubjectnaturalhistory
